How to Install Molding on Bowed Walls

Measure the width of the wall with a tape measure. Transfer the measurement to a piece of molding and make a mark with a pencil.

Cut the molding to the required length with the circular saw.

Repeat steps 1 and 2 for each wall you're adding base molding to.

Lay the piece of molding against the wall, before attaching it, to see if it lays flat or if there are gaps because of a bowed or uneven wall.

Mark where the wall is uneven with the pencil and use the stud finder to find the studs in the wall.

Attach the molding to the bowed or uneven section of the wall. Drive a finish nail into the stud you found in Step 5 with the hammer or use a nail gun.

Insert a shim behind the molding at the location of each stud you found in Step 5. Drive a finish nail into the stud with the hammer or use a nail gun.

Run a utility knife through the shim along the top of the molding. Pull on the shim to break it off and sand the top of the shim with sandpaper to make it smooth.

Apply paintable caulk along the edge of the molding and the wall to cover the gap left by the shim. Smooth the caulk with your finger. Let the caulk dry for 12 to 24 hours.